Hepatitis C infection is still a significant issue in the United States. Nationwide, the number of cases is estimated at 2.7 to 3.9 million. The age distribution is unusual: there is one peak around age 25, and another peak around age 50.
Shauna Onofrey and colleagues at the Centers for Disease Control and Prevention reported these findings from data provided by the Massachusetts Department of Public Health. Non-hispanic whites have the highest rates; males and females are equally affected.
Samina Noorali and colleagues at Claflin University in South Carolina provided a review of this disease. Hepatitis actually has two meanings: (1) inflammation of the liver, and (2) a family of viral infections of the liver. The viruses are identified by letters. Hepatitis A, B, and C are most common in the United States, while D, E, and G are less common. The hepatitis C virus (HCV) is related to viruses that cause yellow fever, dengue, and encephalitis.
HCV is transmitted mainly through blood. Before tests were developed to screen donated blood, transfusions were a common source of HCV infection. Today injection drug use, with sharing of contaminated needles, is believed to cause more than 60 percent of cases. Other transmission routes are organ transplants, accidental needle sticks, sex with an infected partner, and birth to an infected mother.
The incubation period for HCV infection ranges from two weeks to six months. Most patients have no symptoms. Approximately 20 to 30 percent have jaundice, and another 10 to 20 percent have nonspecific flu-like symptoms, including loss of appetite, fatigue, and abdominal pain. The majority, around 70 percent, develop chronic hepatitis, which is a common cause of cirrhosis and liver cancer.
“The progression of chronic liver disease is usually insidious; it is slow and without symptoms or physical signs in most patients during the first two decades after infection,” Noorali explained. Standard treatment is pegylated interferon-alpha in combination with ribavirin. No vaccine is yet available.